Encapsulant for a disc drive component

ABSTRACT

A slider is used in an actuation system and carries a transducing head for transducing data to and from a rotatable recording disc. The slider includes a slider body having a leading edge and a trailing edge and a transducing head positioned proximate the trailing edge of the slider body. An encapsulant comprised of a self assembled monolayer covers exposed surfaces the slider body.

BACKGROUND OF THE INVENTION

The present invention generally relates to a disc drive microactuator.More particularly, the invention relates to an encapsulant covering allexposed surfaces of a component wherein the component may be selectedfrom the group consisting of the microactuator, slider, disc spacer,surface mount component on a printed circuit card assembly, or a ceramiccomponent of a disc drive. The invention further relates to amicroactuator driven by piezoelectric (lead-zirconate-titanate)crystals, the microactuator having improved cleanliness and decreasedparticle generation levels within the drive.

Disc drive systems include disc drive suspensions for supportingtransducing heads over information tracks of a rotatable disc.Typically, suspensions include a load beam having a mounting region on aproximal end, a flexure on a distal end, a relatively rigid regionadjacent to the flexure, and a spring region between the mounting regionand the rigid region. An air bearing slider, which holds the transducinghead, is supported by the flexure. The mounting region is typicallyattached to a base plate for mounting the load beam to an actuator arm.A motor, which is controlled by a servo control system, rotates theactuator arm to position the transducing head over the desiredinformation tracks on the disc. This type of suspension is used withboth magnetic and non-magnetic discs.

The density of concentric data tracks on magnetic discs continues toincrease (i.e., the size of data tracks and radial spacing between datatracks are decreasing), requiring more precise radial positioning of thetransducing head. Conventionally, head positioning is accomplished byoperating an actuator arm with a large-scale actuation motor, such as avoice coil motor (VCM), to radially position the head on the slider atthe end of the actuator arm. The large-scale motor lacks sufficientresolution to effectively accommodate high track density discs. Thus, ahigh resolution head positioning mechanism, or microactuator, isnecessary to accommodate the more densely spaced tracks.

One design for high resolution head positioning involves employing ahigh resolution microactuator in addition to the conventional lowresolution actuator motor, thereby effecting head positioning throughdual stage actuation. Various microactuator designs have been consideredto accomplish high resolution head positioning. These designs, however,all have shortcomings that limit the effectiveness of the microactuator.Many designs increase the complexity of designing and assembling theexisting components of the disc drive, while other designs are unable toachieve the force and bandwidth necessary to accommodate rapid trackaccess. Therefore, those prior designs do not present idealmicroactuator solutions.

More recent microactuator designs employ electroactive elements toeffect movement of the suspension with respect to the actuator arm,i.e., suspension level microactuators, or to effect movement of theflexure with respect to the suspension. In a suspension levelmicroactuator, the electroactive elements generally includepiezoelectric crystal dies attached between a head mounting block (orbase plate) of the actuator arm and the head suspension. Thepiezoelectric elements are typically ceramic PZT crystals and are eithersingle layer or multi-layer (ML) crystals.

In the field of hard disc drives, ceramic (hard) particles are a majorsource of damage to recording heads and the disc media, and the PZTcrystals are a source of ceramic particles within the drive. Inoperation, voltage is applied to the PZT crystals to deform the elementand thereby effect movement of the suspension with respect to theactuator arm. The voltage application to the piezoelectric elementcauses expansion and contraction of the PZT die, which causes ceramicparticles to be ejected from the surfaces and edges of the element. Theparticles are a potential source of damage to the recording head anddisc media and result in hard errors, head failures, and loss of data.

Cleaning has been the primary method for hard particle removal, butcleaning weakens the grain boundaries and allows for more particles tobe freed from the PZT crystal, thereby exasperating the hard particleproblem. Multi-layer PZT crystals also pose an additional problembecause moisture in the drive environment will cause electrode migrationof the Ag—Pd electroding, which can significantly lower the insulationresistance of the ML PZT crystal. This effect will be observed as a lossin stroke performance of the head gimbal assembly over time.

Some prior systems have tried to minimize particles by cleaning of thesuspension assembly in an aqueous or solvent system, but have notsucceeded because the particle reduction plateaus. Other systems useglob-top encapsulants to minimize particles, but such encapsulants arenot useful in a drive environment due to contamination issues andmicroactuator stroke reduction. In addition, some moisture barriertechniques involve embedding the ends of the layered electrodes in thePZT, but this technique minimizes the effective area of the ML crystal,reduces total potential stroke for a given die size, and contributesmore area for particle generation.

Most sliders are composed of alumina titanium carbide (AlTiC), which hasa high energy surface. Incoming, ceramic (hard) particles, moisture andlubricant from the recording media easily adhere or adsorb to the slidersurface. In addition, the composite structure of AlTiC tends to releaseparticles from its grains due to shock and contact events causing drivesto crash or fail when the slider runs over a particle at high speed.

A microactuator and a slider, for example, are needed which minimizeparticles ejected from the PZT crystals during voltage application,prevent particle shedding due to contact events (including load andunload), significantly reduce surface particulate levels, preventincoming particle accumulation, adhesion or agglomeration on surfaces,provide a moisture barrier that does not contribute to hard particlegeneration or lower the insulation resistance in capacitance, mitigatelube pick up from media for recording heads, and improve flyability ofrecording heads with reduced stiction/friction.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to an encapsulant suitable forcovering exposed surfaces of a component. The component may be usable inan actuation system and may be selected from the group consisting of amicroactuator, a slider, a disc spacer, surface mount components on aprinted circuit card assembly, or ceramic components of the disc drive.The encapsulant is comprised of a self assembled monolayer, such as anorganosilane, organosilicone or n-octadecene.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a disc drive actuation system for positioning aslider over tracks of a disc.

FIG. 2 is a top view of a microactuation system for use in a dual stagedisc drive actuation system for high resolution positioning of a slider.

FIG. 3 is a cross sectional view of piezoelectric elements of themicroactuator taken along line 3-3 of FIG. 2.

FIG. 4 is a bottom perspective view of a slider of the presentinvention.

FIG. 5 is a cross sectional view of the slider taken along line 5-5 ofFIG. 4.

FIG. 6 is a cross sectional view of the slider taken along line 6-6 ofFIG. 4.

DETAILED DESCRIPTION

FIG. 1 is a top view of a disc drive actuation system 10 for positioninga slider 12 over a track 14 of a disc 16. Actuation system 10 includesvoice coil motor (VCM) 18 arranged to actuate an actuator arm 20 on aspindle around an axis 22. A head suspension 24, or load beam, isconnected to actuator arm 20 at a head mounting block 26. A flexure 28,or gimbal, is connected to a distal end of head suspension 24, andsupports slider 12. Slider 12 carries a transducing head (not shown) forreading and/or writing data on concentric tracks 14 of disc 16. Disc 16rotates around an axis 30, so that windage is encountered by slider 12to keep it aloft a small distance above the surface of disc 16.

VCM 18 is selectively operated to move actuator arm 20 around axis 22,thereby moving slider 12 between tracks 14 of disc 16. However, for discdrive systems with high track density, VCM 18 lacks sufficientresolution and frequency response to position the transducing head onslider 12 over a selected track 14 of disc 16. Thus, a higher resolutionmicroactuation device is used to finely position slider 12, as shown inFIG. 2.

FIG. 2 is a top view of a microactuation system for use in a dual-stagedisc drive actuation system for high resolution positioning of slider12. In particular, FIG. 2 shows a suspension level microactuator 32.Head mounting block 26, or the base plate, is attached to a distal endof actuator arm 20 (not shown). Head suspension 24 is attached to headmounting block 26 by microactuator 32. A distal end 34 of headsuspension 24 is attached to flexure 28 and applies a preload force toslider 12 at a load point to force slider 12 into close proximity with asurface of disc 16 when the disc drive is in operation. Slider 12 isattached to flexure 28 by a tongue at a distal end of flexure 28.

The microactuator 32 includes a compliant connection joint 36 forconnecting head suspension 24 to head mounting block 26. Head mountingblock 26, head suspension 24, and compliant joint 36 may be formed of asingle sheet of material. In the embodiment shown in FIG. 2, compliantconnection joint 36 is comprised of two beams located between headsuspension 24 and head mounting block 26.

Microactuator 32 further includes piezoelectric elements 38 a and 38 bmounted to head mounting block 26 and head suspension 24, generallyparallel to compliant joint 36. Piezoelectric elements 38 a and 38 b aredeformable longitudinally in response to control signals, an appliedvoltage, across the elements. Expansion and contraction of piezoelectricelements 38 a and 38 b results in deformation of compliant joint 36,causing rotation of head suspension 24 and slider 12 with respect tohead mounting block 26, and thereby effecting high resolutionpositioning of the transducing head carried by slider 12. Complementaryexpansion and contraction of piezoelectric elements 38 a and 38 b in thedirection of arrows 40 and 42, respectively, generate force which causeselastic deformation of compliant joint 36, resulting in rotational rigidbody movement of head suspension 24 around joint 36 in the direction ofarrow 44.

Piezoelectric elements 38 a and 38 b are generally comprised of PZT(lead-zirconate-titanate) crystal dies having a single layer ofpoly-crystal material or a multi-layer (ML) comprised of multiple, thinlayers of poly-crystal material with electroding between each layer.

Also shown in FIG. 2 is a printed circuit card assembly (“PCCA”) 43,which operates as an additional component in the disc drive. Trace 45electrically connects the slider to PCCA 43. The microactuation systemincludes several components, including ceramic components, such asslider 12 and disc spacers, and stainless steel components, such as headmounting block 26, head suspension 24, flexure 28, or actuator arm 20.

FIG. 3 is cross sectional view of microactuator 32 taken along line 3-3of FIG. 2. Each piezoelectric element 38 a, 38 b of the microactuationsystem has a top surface 46 and a bottom surface 48, with bottom surface48 being attached to head suspension 24 and head mounting block 26 by aconductive epoxy 49. Both top and bottom surfaces 46, 48 include anelectrode 50 a and 50 b (typically gold), to provide an electricalinterconnect between the disc drive and head suspension 24. Topelectrodes 50 a provide an electrical connection to apply voltage topiezoelectric elements 38 a, 38 b and actuate head suspension 24.

During operation of microactuator 32, voltage is applied topiezoelectric elements 38 a and 38 b to cause expansion and contractionof the PZT crystal dies, which results in the ejection of ceramic hardparticles from the hard surfaces and edges of the PZT dies. The ejectedparticles are a major source of damage to recording heads and discmedia, and result in hard errors, head failures and loss of data. Thepresent invention is an encapsulant covering all exposed surfaces ofpiezoelectric elements 38 a and 38 b within the microactuation system toprevent particle generation during operation of microactuator 32. Theencapsulant also serves as a moisture barrier for ML PZT die bypreventing water vapor from reaching the electrodes and causingcorrosion of the electrodes.

As shown in FIG. 3, an encapsulant 52, or polymer coating, covers allexposed surfaces of piezoelectric elements 38 a, 38 b (i.e., allsurfaces except bottom surface 48) attached to head suspension 24 andhead mounting block 26. Polymer coating 52 is preferably applied topiezoelectric elements 38 a, 38 b prior to placement of piezoelectricelements 38 a, 38 b within the suspension assembly. Encapsulant 52 maybe applied to piezoelectric elements 38 a, 38 b using various coatingtechniques, such as, but not limited to, dip or gravity flow coating,spray coating, spin coating, screen coating, roll coating, or vapordeposition. After coating piezoelectric elements 38 a, 38 b, polymercoating 52 is generally cured to facilitate cross linking of thepolymer. Subsequent curing depends on the type of the polymer used, butusually consists of various curing techniques, such as, but not limitedto heat, ultra-violet, or electron beam. Cross linking the polymerinhibits encapsulant 52 from becoming mobile during actuation andthereby restricts particles on the surface of elements 38 a, 38 b frombecoming mobile. Once polymer coating 52 is fully cured, measuredparticles on the surface of elements 38 a, 38 b are reduced and theencapsulant acts as a moisture barrier to prevent corrosion ofelectrodes 50 a, 50 b. The polymer of encapsulant 52 has a minimalelastic constant such that it does not restrict motion of piezoelectricelements 38 a, 38 b and is electrically non-conductive.

Encapsulant 52 has a thickness of one micron or less so as to notrestrict the motion of piezoelectric elements 38 a, 38 b or inhibitelectrical connection to top electrode 50 a via soldering. Morepreferably, the thickness of encapsulant 52 is between 25 and 30angstroms. The thin coating does not affect performance of piezoelectricelements 38 a, 38 b, (e.g., stroke performance or electricalperformance). Furthermore, coating 52 is thin enough so that anelectrical connection may be made to top electrode 50 a by solderingwithout degrading the surrounding encapsulant and/or requiring laserablation.

In one embodiment, encapsulant 52 is comprised of a polymer coating suchas a fluorocarbon polymer, parylene, or an epoxy. More preferably, thepolymer is a fluoroacrylate or perfluoropolyether, such as EGC-1700® orFomblin Z-Tetraol® (manufactured by Ausimont of Italy).

One example of polymer coating 52 is Tetraol®, or other fluoroacrylatesor perfluoropolyethers. The fluoropolymers are generally applied topiezoelectric elements 38 a, 38 b with one of several coating processes,such as dip or gravity flow coating, spray coating or spring coating, toachieve a thin uniform coating. Polymer coating 52 has a thicknessbetween 10 to 100 angstroms, depending upon the concentration of thecoating solution and the method of coating used.

Curing cross links the polymer chains to provide a more robust andadhered coating. Curing can take the form of either heat, ultra-violet,or electron beam, depending upon the polymer used. However, the mostpreferred method of curing for fluoropolymers is electron beam. In theelectron beam cure process, electrons are distributed uniformlythroughout the coating with energies that can extend to several kiloelectron volts (keV), which are much higher energies than theultra-violet process. An electron beam vacuum cure has energies between20,000 and 80,000 micro Coulombs per centimeter squared (μC/cm²) and anelectron beam air or nitrogen cure has energies between 80,000 and250,000 kilo Grays (kGry).

With fluoropolymers, uniformity of coating is achieved at 20 or moreangstroms to allow for reduced liquid particle counts (LPC), minimizedparticle generation, and reduced degradation in ML PZT crystal strokefrom water vapor penetration. In addition, fluoropolymers encapsulantscan be soldered through to provide an electrical connection to thepiezoelectric element.

A further example of polymer coating 52 is a parylene polymer appliedusing vapor deposition. The parylene is coated at a thickness between0.5 microns and 1 micron, such that significant reduction in liquidparticle counts are observed and no reduction in insulation resistanceis monitored from lifetime testing of ML PZT crystals. Electricalbonding to the piezoelectric element is achieved by maintaining a thinparylene coating or by selectively removing the parylene by abrasion orlaser ablation. Parylene coatings reduce the amount of particlesextracted from the PZT crystal during liquid particle count. Parylene isalso an effective moisture barrier and prevents water vapor fromreaching the electrodes, which would cause dendritic growth of theelectrodes and corrosion under applied voltage.

Another example of polymer coating 52 used in the present invention isepoxy polymers. Epoxy is applied with one of several coating processes,such as, dip or gravity flow coating, spray coating, spin coating, orroll coating, to achieve a thin uniform coating. The epoxy coating iscured thermally at various temperatures.

In further embodiments of the present invention, encapsulant 52 iscomposed of a self assembled monolayer (SAM), which covers exposedsurfaces of piezoelectric elements 38 a, 38 b. One example is a SAM ofthin organic film selected from the family of organosilicone, ororganosilanes, including octadecyltrichlorosilane (OTS),octadecyldimethylchlorosilane, butyltrichlorosilane,perfluorodecyltrichlorosilane, alkylsiloxane, alkyl andperfluoroalkyl-trichlorosilane, dichlorosilane, alkene and alkyl ethoxysilanes, octadecyltriethoxysilane, alkylaminosilanes, and alkanethiols.In further embodiments of the encapsulant, n-octadecene is used as aSAM. SAMs are self-limiting to one layer and adhere to piezoelectricelements 38 a and 38 b, or other selected components, to form a onelayer film covering the component. Encapsulant 52 has a self limitingthickness of one layer of a molecule, which is between about 10angstroms and about 40 angstroms, and most preferably between about 28angstroms and about 30 angstroms.

Self assembled monolayers are self-cross linking and do not require anadditional step of curing to adhere encapsulant 52 to the component.SAMs are two-dimensional structures that link to itself and otherstructures. For example, organosilanes will only adhere to ceramicmaterials, especially ceramic oxides, such as those forming slider 12,piezoelectric elements 38 a and 38 b, disc spacers, surface mountcomponents on a printed circuit car assembly and other components of theactuation system. In some embodiments of the present invention heatannealing at temperatures between about 100° C. and about 200° C. may beused.

Encapsulant 52 is applied to any area of a component that requiresprotection from moisture, hard particle generation, or particleaccumulation. Two exemplary methods of applying a SAM encapsulant 52 tothe component are dip coating and chemical vapor phase deposition (CVD),although other coating techniques known in the art may be used. SAMs ofthin organic film, in particular organosilanes, selectively adhere tocertain materials (e.g., ceramics) where applied to a component whileleaving other materials exposed (e.g., metals or carbon). Thus, duringthe coating process the SAMs will only adhere to some portions of thecomponent and will not adhere to other portions. In both a dip coatingand a CVD coating process, the SAM is dissolved in a solvent, such asn-hexane, n-cylohexane, aromatic hydrocarbons (such as toluene), halogencompounds (such as chloroform), and branched hydrocarbon solvents.Silanization of a substrate (e.g., a slider, microactuator or otherceramic component) results in hydrolysis of a polar head group whichturns Si—Cl bonds to Si—OH groups, which then attach to a ceramic oxidesurface reacting with the Si—OH (or silanol). The surface of thesubstrate has a low energy hydrocarbon tail, with water contact anglesgreater than 110°.

The present invention includes a polymer coating encapsulant coveringall exposed surfaces of a piezoelectric element of a microactuationsystem. The polymer coating provides a moisture barrier to prevent watervapor from reaching the electrodes of the piezoelectric element, whichwould cause dendritic growth of the electrodes, corrosion under appliedvoltage, and lower insulation resistance capacitance. In addition, theencapsulant as a moisture barrier does not contribute to hard particlegeneration. The present invention encapsulant allows for free movementof the PZT crystal, in addition to locking particles at thepiezoelectric surface. Furthermore, the polymer coating reduces theamount of particles extracted during liquid particle counts and duringvoltage application to the piezoelectric element (i.e., the liquidparticle counts and aerosol particle counts are lowered and the particlegeneration from the piezoelectric elements is minimized). The presentinvention is a cost effective way of reducing contamination in the discdrive for microactuator components because the application and curing ofthe encapsulant can be performed inline during manufacture of thepiezoelectric elements. Furthermore, the present invention is a uniqueway to prolong the product life of ML PZT in the disc drive environmentbecause of the moisture barrier capabilities.

The present invention encapsulant is also effective as a coating forother components of the actuation assembly to prevent hard particlegeneration within the assembly, incoming particle accumulation onsurfaces, mitigate lube pick up from media and improve flyability oftransducing heads. The encapsulant covers exposed surfaces of componentsof the disc drive, such as the microactuator, the slider, a disc spacer,surface mount components on a printed circuit card assembly, any ceramiccomponent of the disc drive assembly or any stainless steel component ofthe disc drive assembly, such as the head mounting block, load armassembly, flexure or actuator arm.

FIG. 4 is a bottom perspective view of slider 12 carrying transducinghead 60. Slider 12 includes a slider body 62 having a leading edge 64and a trailing edge 66 with transducing head 60 positioned at trailingedge 66. Positioned along trailing edge 64 are slider bond pads 68 andinterconnects 70 formed between transducing head 60 and slider bond pads68. Slider bond pads 68 and interconnects 70 are composed of a metallicmaterial, although other conductive materials may be used.

FIGS. 5 and 6 are cross sectional views of slider 12 taken along line5-5 and line 6-6, respectively, of FIG. 4 illustrating selectiveadhesion properties of encapsulant 72. Slider 12 is coated withencapsulant 72, which in the embodiment shown in FIGS. 5 and 6 is a SAMthat selectively adheres to specific exposed surfaces of slider body 62.Slider body 62 is composed of alumina titanium carbide (AlTiC), siliconor other ceramic material whereas transducing head 60, slider bond pads68 and interconnects 70 are composed of a substantially metallicmaterial.

Encapsulant 72 is applied to slider 12 by dip coating, vapor phasedeposition, or other know coating techniques. SAMs selectively adhere tocertain materials forming slider 12 to coat the slider with a thin onelayer film. For example, organosilanes, a preferred SAM of the presentinvention, only adhere to ceramic materials, such as those that compriseslider body 62, microactuator 32, disc spacers surface mount componentsand other ceramic components of the actuation system. Thus, as shown inFIG. 6, encapsulant 72 coats the exposed ceramic portions of slider 12,such as slider body 62, and does not coat the non-ceramic portions,including diamond like carbon materials, such as transducing head 60,slider bond pads 68 and interconnects 70, which remain exposed. Slider12 is not be completely covered by encapsulant 72 to maintain aconductive path and mitigate head/media separation problems.

The present invention encapsulant composed of a SAM provides a thinsingle layer film to protect components of an actuation system,including the slider, microactuator, disc spacer, surface mountcomponents and ceramic components of the system. An encapsulated sliderprevents particle shedding due to contact events (including load andunload), prevents incoming particle accumulation, adhesion oragglomeration on surfaces, provides a moisture barrier, mitigates lubepick up from media for recording heads, and improves flyability ofrecording heads with reduced stiction/friction. By coating orencapsulating AlTiC portions of a slider, the surface energy is loweredand mitigates external disturbances, such as external particles,contaminants, and moisture. In addition, the encapsulating film preventsshedding or release of internal particles during operation (e.g.,contact events), creates softer edges, corners and surfaces, and fillsin cracks and gaps in the slider substrate. The low surface energyprovided by the encapsulant provides a lubrication layer such that theslider has improved flyability over media and improved stiction andfriction.

Although the present invention has been described with reference topreferred embodiments, workers skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the invention.

1. An improved actuation system for positioning a slider carrying atransducing head, the actuation system of the type having a movableactuator arm, a head suspension, a microactuator, a flexure, a sliderand a transducing head carried by the slider, the improvementcomprising: an encapsulant comprised of a self assembled monolayer witha self limiting thickness of one layer of a molecule covers an exposedsurface of a component selected from the group consisting of themicroactuator, the slider, a disc spacer, surface mount components on aprinted circuit card assembly, and ceramic components of the actuationsystem; wherein the self assembled monolayer is composed of anorganosilane selected from the group consisting ofoctadecyltrichlorosilane (OTS), octadecyldimethylchlorosilane,butyltrichlorosilane, perfluorodecyltrichlorosilane, alkylsiloxane,alkyl and perfluoroalkyl-trichlorosilane, dichlorosilane, alkene andalkyl ethoxy silanes, octadecyltriethoxysilane, alkylaminosilanes, andalkanethiols.
 2. The improvement of claim 1 wherein the encapsulant hasa thickness in the range of about 10 angstroms to about 40 angstroms. 3.The improvement of claim 1 wherein the encapsulant selectively adheresto exposed ceramic surfaces of the component.
 4. The improvement ofclaim 1, wherein the microactuator comprises: a first piezoelectricelement attached between a mounting block and the head suspension, thefirst piezoelectric element being deformable in response to a voltageapplied thereto; a compliant joint between the mounting block and thesuspension, the compliant joint being flexible to permit movement of thesuspension with respect to the mounting block; and wherein theencapsulant comprises a self assembled monolayer covering a surface ofthe first piezoelectric element.
 5. The improvement of claim 4 whereinthe self assembled monolayer is composed of an organosilane.
 6. Theimprovement of claim 5 wherein the organosilane is selected from thegroup consisting of octadecyltrichlorosilane (OTS),octadecyldimethylchlorosilane, butyltrichlorosilane,perfluorodecyltrichlorosilane, alkylsiloxane, alkyl andperfluoroalkyl-trichlorosilane, dichlorosilane, alkene and alkyl ethoxysilanes, octadecyltriethoxysilane, alkylaminosilanes, and alkanethiols.7. The improvement of claim 4 wherein the self assembled monolayer iscomposed of N-octadecene.
 8. The improvement of claim 4 wherein theencapsulant has a thickness between about 10 angstroms and about 40angstroms.
 9. The improvement of claim 4 wherein the encapsulantselectively adheres to exposed ceramic materials of the firstpiezoelectric element.
 10. The improvement of claim 4, and furthercomprising a second piezoelectric element attached between the mountingblock and the suspension, the second piezoelectric element being coveredby an encapsulant comprised of a self assembled monolayer and deformablein a direction complementary to deformation of the first piezoelectricelement in response to a voltage applied thereto.
 11. An improvedactuation system for positioning a slider carrying a transducing head,the actuation system of the type having a movable actuator arm, a headsuspension, a microactuator, a flexure, a slider and a transducing headcarried by the slider, the improvement comprising: an encapsulantcomprised of a self assembled monolayer with a self limiting thicknessof one layer of a molecule covers a surface of a component selected fromthe group consisting of the microactuator, the slider, a disc spacer,surface mount components on a printed circuit card assembly, and ceramiccomponents of the actuation system; wherein the self assembled monolayeris composed of N-octadecene.
 12. A slider comprising: a slider bodyhaving a leading edge and a trailing edge; a transducing head positionedproximate the trailing edge of the slider body; and an encapsulantcomprised of a self assembled monolayer with a self limiting thicknessof one layer of a molecule covering an exposed surface of the sliderbody; wherein the self assembled monolayer is composed of anorganosilane selected from the group consisting ofoctadecyltrichlorosilane (OTS), octadecyldimethylchlorosilane,butyltrichlorosilane, perfluorodecyltrichlorosilane, alkylsiloxane,alkyl and perfluoroalkyl-trichlorosilane, dichlorosilane, alkene andalkyl ethoxy silanes, octadecyltriethoxysilane, alkylaminosilanes, andalkanethiols.
 13. The slider of claim 12 wherein the encapsulant has athickness in the range of about 10 angstroms to about 40 angstroms. 14.The slider of claim 12 wherein the encapsulant is substantially uniform.15. The slider of claim 12 wherein the encapsulant selectively adheresto ceramic surfaces of the slider body.
 16. The slider of claim 12wherein the encapsulant is applied to the slider by dip coating, gravitycoating, spray coating, screen coating, roll coating or vapor phasedeposition.
 17. A slider comprising: a slider body having a leading edgeand a trailing edge; a transducing head positioned proximate thetrailing edge of the slider body; and an encapsulant comprised of a selfassembled monolayer with a self limiting thickness of one layer of amolecule covering a surface of the slider body; wherein the selfassembled monolayer is composed of N-octadecene.